Electric switch



July 2, 1940. K. c. ALLISON ET A}.

ELECTRIC SWITCH Filed June 19, 1937 3 Sheets-Sheet l July 2, 1940. K. c. ALLISON ET AL 2,206,655

ELECTRIC SWITCH Filed June 19, 1937 3 Sheets-Sheet 2 fieffz fa 15 67222627 6. Za/z/Jf/J%asg wimy July 2, 1940. K. c. ALLISON Er AL 2,206,655

ELECTRIC SWITCH Filed June 19, 1937 3 Sheets-Sheet 3 Patented July 2, 1940 UNITED STATES nmo'rmo swrrcn Kenneth 0. Allison, Arlington Heights, and Edward J. Mastney, Berwyn, llL, assignors to Oak Manufacturing Company, Chicago, Ill., a

corporation of Illinois Application June 19, 1931, Serial No. 149,140

1 Claim. (01. 200-15) This invention relates to electric switches and more particularly to small compact switches such as are used in radio receivers and similar devices. It is a desirable feature to provide a switch with an index action so designed that the parts fit compactly together to make an assembly which will take up a minimum of room. Because of the delicacy of the circuits controlled, it is also necessary that the switching action be uniform over a substantially-long useful life. Flexibility with regard to switching combinations is also important.

Referring to the drawings: Figure 1 is a top view of one form of a switch. Figure 2 is a side view of the same switch. Figure 3 is a bottom view of the switch. Figure 4 is a section on line 4-4 of Figure 3. Figure 5 an enlarged sectional detail illustrating the switching action.

Figure 6 is a section on line 68 of Figure 5. Figure '7 is a top view of a modified form of switch.

Figure 8 is a bottom view of the same switch. Figures 9 to 11 inclusive are details of parts of the switch assembly.

Figure 12 is a top view of another modification.

Figure 13 is a bottom view of the switch of igure 12.

Figure 14 is a top view of still another modiflcation.

Figure lfi is a section on line |5 |5 of Figure 14.

Figure 16 is a bottom view of the switch of Figure 14.

Figures 17 and 18 are top and bottom views of an additional modification.

Referring to Figures 1 to 4 inclusive, the switch comprises a bushing ID of any metal such as brass or iron, having a shoulder H. I Beyond shoulder it a thin sleeve-like portion 52 is provided. Bushing i0 is adapted to support an index plate |3 immediately against shoulder i3 is preferably of stamped sheet metal and has an end portion thereof bent to form a finger I4. Index plate l3 has one or more bumps l5 formed thereon, while on each side of the bumps and acting as stops, are fingers I6 and I1 bent upwardly as viewed in Figure 4.

Supported above index plate I3 is an insulating stator 20 of any rigid material such. as Bakelite. The stator is adapted to fit snugly around portion l2 of the bushing and in order to maintain the bushing index plate and stator intact, the end 2| of the bushing is rolled over against the stator material to hold the same tightly in position. As shown in Figure 1; stator 20 is of a generally rectangular shape and eccentrically mounted so as to leave a portion 23 for switching purposes. A pair of apertures 24 and 25 are provided in the stator and these are preferably Index plate.

located on the circumference of a circle concentric with bushing l0. Each aperture 24 and 25 may have mounted therein a stationary contact 26 maintained inposition by an eyelet 21. Contact 26 is preferably formed of spring metal doubled over to form a soldering lug 28, a mounting portion 29 and a contacting portion 30. Contacting portion of jaws 3| and to permit lower therein.

As is clearly seen in Figure 5, contact jaw 3| comprises a bent hinge portion immediately adjacent mounting portion 29 of the clip. Hinge portion 35 as shown in the figure, is bent upwardly at a rather large angle from the stator 20 and thereafter, upper jaw 3| proper is bent downwardly. The side tips 36 and 31 (Figure 3) are bent upwardly leaving the center portion 38 of the jaw edge as the contact making portion thereof. V

Lower jaw 32 has a doubly curved hinge portion comprising an upwardly bent portion 40 and a downwardly bent portion 4| extending from the mountingportion 29 of the clip. Upwardly bent portion 40 as shown in 30 is shaped to provide a pair 32. Stator 20 is apertured at 33 jaw 32 of the contact to operate Figure 5, is more rounded and smaller in extent- 7 than the upper contact hinge portion. The I lower bent portion 4| causes the spring material to'extend Well into aperture 33 of the stator. The lower jaw 32 then extends upwardly from lower hinge. portion 4|. The extreme jaw edges of the lower portion 32 are shaped in the same manner as the upper jaw 3|.

Rotatively disposed within bushing I0 is a shaft having a circular slot 46 which is normally adapted to go near the end of bushing E0. The shaft is maintained in position longitudinally by means of a C washer 41. Shaft 45 extends through bushing I0 and beyond-the stator 20, the aperturing portion of the shaft beyond the stator, is squared at 48 and is adapted to carry a metallic member functioning as a combined rotor contact and index spring. The end of the shaft is peaned over at 49 to hold member 50 rigidly on the shaft. Member 50 is preferably of some suitable metal such as phosphor bronze or spring copper and comprises a portion 5| functioning as a rotor contact and a portion 52 bent over to forma finger 53 functioning as an index spring. Portion 52 is adapted to cooperate with bump i5 on the index plate and is limited in its travel by end stops l6 and I! so that a definite index action results.

Contact portion 5| is preferably wider than apertures 33 in the stator and is preshaped so that the end edge 5| tends to press tightly against stator 20. In the normal operation of the switch, theside edge of contact portion 5| is adapted to enter the distended tips of the stator contacts and go open these contacts to enter between he opposing jaws. As is well understood, the spring stator Jaws tend to close at all times. In the normal mounting of the stator Jaws, the jaws tend to meet in a line just slightly above the surface of statorlfl. By having the rotor end edge of H pressed tightly against the stator material, and

by having the contact portion of ti slope away from stator the entering side edge oi contact portion 5I will always enter the jaws at their mally tend to spring the stator contacts beyond the elastic limit unless some control over the rotor contact spring force were present. By the provision of the apertures in the stator and having the rotor contact wider than the aperture,

the insulating material of the stator takes up the pressure of the rotor contact spring. 1

Referring to Figures '7 and-8, a switch is shown wherein the rotor contact 15 is provided with opposed contact blades 16 and ll and an index spring 18 at right angles thereto. I In this construction, the stator 80 is provided with opposing sets of stator contacts.

In Figures 9 to 11 inclusive, a modified construction of bushing is shown wherein the parts align themselves automatically. Inthis construction bushing I00 has its end portion IIJI slotted at diametrically opposed points I02 and I03. This slotting may be done in automatic screw machines. An index plate m5 is provided with an aperture I06 having opposed tongues Ill! and I08 so shaped as to lock on bushing I00 when fitted together. Stator III) is also apertured at I I I and has tongues I I2 and I I3 so that the entire assembly will go together in perfect alignment. The edge portion IIII of the bushing may then be rolled over against stator I IE! to hold the assembly in position.

Referring to Figures 12 and 13, a three position switch is shown in which the index plate H5 is provided with a pair of bumps H6 and H1 and .end stops H8 and H9. It is obvious that the .angle travel of the rotor may be enlarged with this construction up to a maximum or around 180 degrees. It is also possible to provide as many index positions. as may be desired within this range of travel.

Referring to Figures 14 to 18 inclusive, the switches there shown are the type wherein the rotor contact is not grounded. The previously,

described constructions have all had the rotor contact directly mounted on the operating shaft so that a grounded switch resulted. It is, however, desirable in many cases to provide a switch where two or more poles thereof are insulated from ground. To this end, shaft I has a squared end portion I3I extending above stator I32. Mounted on this squared portion is an insulating rotor disc I33 preferably circular and having a plurality of apertures I34 disposed near the edge thereof. one or more contacts I35 may be provided. These contacts are flat and have fingers I36 along the "inner portions thereof. These fingers are adapted to be threaded through one or more of the apertures I34 and tend to maintain the contact rigidly on rotor disc I33. As shown in Figure 15, rotor contacts I35 are preferably mounted on the side of the rotor disc nearest stator H32 and extend well toward the stator contacts so as to slide therebetween. Normally, rotor disc ltd is so mounted that a slight clearance between rotor contacts I35 and stator I132 is present. The index springarm is mounted directly on the shaft and, as shown in Figures 14 and 15, index arm GM is mounted on a squared portion till 01? the shaft. This squared port-ion Iltl is smaller than the'squared portion itl tor the rotor disc, m that index arm IGI is held above rotor disc i328 providing clearance enough to allow floating of the rotor disc longitudinally along its squared portion I3I of shaft t3iI.- At the same time location of index arm I-Iil above rotor disc I33 is such that the longitudinal movement of rotor disc is limited within the range permitted by the flared sides 36 and 31 of clips; This is particularly important when clip arrangement is such that in some one position of the switch, clips are engaging rotor contacts only on .one side of the switch. In the form shown in Figures 14 to 16, inclusive, stator I32 is provided with opposed sets of three stator contacts each. However, the insulated rotor construction may be modifiedin the same manner as the preceding rotor structures and in Figures 17 and 18, only one series of stator contacts is shown. In this case, rotor disc I53 has a single contact I54 cooperating with stator contacts I55 to I51 inclusive.

What is claimed is:

An electric switch comprising a pair of relatively movable assemblies, one assembly including a rigid insulating base member having a flat face, at least one spring contact carried by said member, said contact comprising a pair of opposed spring jaws with one jaw disposed in a recess in said member and the other jaw disposed beyond the member face, said jaws normally meeting outside of said member face plane'and adapted to be separated during. switching operation to force the one jaw deeper into the recess and the other jaw away .from said member face, the other assembly including a rigid contact adapted to slide between the spring contact jaws, means for mounting said rigid contact on said assembly so that only an edge bears against said base member along the face thereof in all switch positions, means on each of said assemblies adapted to coopcrate fr producing an index action, one of said means including a spring member and the other including a plate having index indentations, said means being so disposed that the index movement occurs in a plane substantially parallel to the rigid contact, the spring of said index means cooperating with said index plate to produce a force substantially perpendicular to the plane of said rigid contact, said rigid contact and the corresponding index means carried by said assembly being formed as one unitary member.

KENNETH. C. ALLISON. J. MASTNEY. 

